feat: initial commit

src/__tests__/observe.spec.luau

@@ -0,0 +1,33 @@
+local atom = require(script.Parent.Parent.atom)
+local observe = require(script.Parent.Parent.observe)
+
+return function()
+	it("observes lifetime", function()
+		local itemsAtom = atom({ "a", "b", "c" })
+		local state = {}
+
+		local cleanup, flush = observe(itemsAtom, function(item, key)
+			state[key] = item
+			return function()
+				state[key] = nil
+			end
+		end)
+
+		for key = 1, 3 do
+			expect(state[key]).to.equal(itemsAtom:get()[key])
+		end
+
+		itemsAtom:set({ [4] = "d", [5] = "e", [6] = "f" })
+		flush()
+
+		for key = 1, 6 do
+			expect(state[key]).to.equal(itemsAtom:get()[key])
+		end
+
+		cleanup()
+
+		for key = 1, 6 do
+			expect(state[key]).to.equal(nil)
+		end
+	end)
+end